Faculty Research

Stephen Cessna

Plant Stress Physiology and Cellular Biochemistry

Plants in nature are continuously subject to several environmental insults, including drought, heat, cold, toxic pollution, disease, and insects. While some plants have evolved the ability to specifically combat one or more of these stresses, (as cacti have special abilities to withstand drought), all plants have adaptive ability to tolerate most stresses to varying degrees. This is achieved at the cellular level by the transcription of specific stress-activated genes. My research project focuses on the roles of calcium and hydrogen peroxide in activating these stress-activated genes. Students working on this project may have the opportunity to learn several different laboratory techniques including: greenhouse maintenance of unique plants, plant cell culture, luminometry, fluorimetry, fluorescence microscopy, and plant genetic manipulation.

Physical Biochemistry of Serum Albumins

Albumin, the most prominent protein in blood serum, is believed to transport fatty acids, drug compounds, vitamins, and toxins through the blood stream. We use fluorescence spectroscopy to determine how well small molecules bind to serum albumin. The small molecules we are currently testing are the B vitamin folic acid and an herbicide called 2,4-D.

These studies have relevance to the fields of nutrition and toxicology.

Jeff Copeland

Molecular Biology of Aging

Much of the aging process and many neurological diseases result from accumulated cell death and the accompanying loss of tissue function, but precious little is known about the genes that determine cellular aging. I am interested in using the fruit fly Drosophila melanogaster as a model to understand the aging process and the genes responsible for it.

Similar to humans, fruit flies show many hallmarks of aging: reduced mobility, forgetfulness, disrupted sleep patterns, decreased reproduction, and the loss of brain cells. Mitochondria are dynamic bacteria-like inhabitants found in nearly all non-bacterial organisms and produce virtually all of the energy needed by the cell. Previous work of mine has shown that a partial decrease in the energy-producing capabilities of mitochondria can extend fly lifespan up to 50%. Interestingly these mutant flies show little cost to longevity – they reproduce, fly, climb like normal flies.

I am interested in further exploring the global role of the mitochondria in aging by manipulating mitochondrial function in specific cell types and by altering other essential mitochondrial functions.

In addition to producing energy for the cell, mitochondria do a number of other important and interesting things. They sometime fuse or split apart, they produce heat, they store calcium, and they help to regulate cell death. By manipulating the genes involved in these other mitochondrial functions, I can discover whether any of these individual processes play a role in cellular aging.

Julia Halterman

How Diet Affects Gene Expression in Hypertension

Currently in the United States, 1 out of 3 adults suffer from hypertension (chronic high blood pressure). It is well understood that eating a diet high in salt can increase the risk and prevalence of hypertension, but it still remains unclear as to how dietary salt affects organ function at the molecular level.

My previous research, along with the research of others, has shown that when salt is applied to cells in a dish, a protein called nuclear factor of activated T-cells 5 (NFAT5) is activated to turn on genes that protect cells from damage. However, this protein is also known to turn on genes involved in disease. Research in my lab therefore seeks to answer the following question: Does eating a diet high in salt increase NFAT5 levels in the body, therefore leading NFAT5 to turn on genes involved in hypertension?

By putting rats on an intermediate-salt or high-salt diet for 6 weeks, we can investigate how tissues respond by measuring changes in NFAT5 levels. Blood pressure will be monitored in rats given an antibody to block NFAT5 to determine if this will inhibit diet-induced increases in blood pressure. Computational data analysis will allow us to discover new genes turned on by NFAT5 in hypertension, thereby providing insight for future drug development and treatment of the disease.

Undergraduate Biology majors and MA in Biomedicine graduate students assisting with this research will have the opportunity to learn how to carry out animal studies, collect blood pressure measurements, dissect tissues and organs, purify RNA from tissue samples, create cDNA, and run quantitative RT-PCR experiments. All of these skills will sharpen the ability to think like a biologist and will better prepare those pursuing a career in medicine or research science.

Roman Miller

Research in Organic Blueberry Production: Horticulture, Product, and Health

My 2014-16 research includes three areas related to blueberries: horticulture quality, product development, and health benefits. I am willing to accept several students to work on specific aspects of these projects. Rising sophomores or juniors are given preference in selecting research participants. These projects carry academic credit and if completed may fulfill the research requirement for biology majors. Learn more…

Doug Graber Neufeld

Environmental Toxicology and Biomonitoring; Water Quality and Pesticide Residue Analysis

My research projects focus on pollutants in the environment. These projects fall within my broader interests of environmental physiology-the study of how animals survive in their diverse environments, how that physiology is altered by environmental contaminants, and how this information can be utilized for monitoring of environmental impacts.

I take two general approaches to studying environmental contaminants. First, I’m interested in the physiological mechanisms of animal exposure to toxic compounds in their environments, with a focus on invertebrates (insects and clams). In particular, my lab uses physiological and biochemical responses of animals as biomonitors to indicate the degree of contamination that is present in the environment. In the past, we used such a biomonitoring approach with Asiatic clams to measure the effects of mercury contamination on local watersheds.

My second area of interest is in direct monitoring of chemical and biological contamination in aquatic ecosystems, sewage treatment systems and drinking water. This work has taken place both on the regional level, and in Southeast Asia. Locally, Dr. Tara Kishbaugh and I are working with students to gather baseline water quality information in an area of northwest Rockingham County. There is the possibility that this region of the county would become the first area in Virginia in which hydrofracking occurs. Should hydrofracking occur, our watershed and drinking water data will give a baseline from which to compare post-hydrofracking samples, in order to assess the extent of any contaminant releases. Our work in Cambodia and Thailand has focused on several issues. We collaborated with IDE Cambodia to measure arsenic content in clay samples that are used to make local drinking water filters. Also, we have collaborated with the Royal University of Phnom Penh, and RDI Cambodia to measure pesticide levels in market vegetables. My recent work on pesticides has focused on the development of a simpler method to both extract and detect pesticides.

Jim Yoder

The Spread of Invasive Exotic Plant Species and Their Impact on Rare Plant Populations in Shenandoah National Park

In the spring of 2006 I began a 3-year collaborative study working with Shenandoah National Park research botanist, Wendy Cass. The project includes both intense on-site field surveying and mapping and analysis of exotic plant spread and impact using a Geographic Information System (GIS) by myself and undergraduate research students.

The project addresses two specific research questions that focus on the exotic plants invading the Shenandoah National Park: 1) What is the rate of spread of the three most threatening exotic species beginning to invade the Big Meadows Swamp Natural Heritage area and 2) What is the impact of these exotics on the continued viability of the eight rare plant species located within the area?

Both of the questions are of intense interest to park biologists and land managers as well as contribute to the broader ecological study of exotic plant invasions of native ecosystems.

Data collected will be used for detailed analysis of rare plant populations as well as development of spatial population and threat models using GIS. These models may be useful to predict future spread of exotics and subsequent impacts on ecologically sensitive areas within the park and throughout the region.

Matthew Siderhurst

Insect Chemical Ecology

Chemical signals are among the most used information transfer sources in ecology and they can include pheromones (conspecific signaling), plant-herbivore interactions, and predator-prey interactions. While many of these chemical signals are of basic scientific interest, they are also increasingly important to developing ecologically rational pest control strategies, both as replacements for pesticides against established pests and to help mitigate the increasing threat of invasive species (damage ~$137 billion/annually). My research focuses on arthropod chemical ecology, applying the tools of organic chemistry to ecological interactions. Currently I am collaborating with colleagues in Hawaii on research involving attractants for tephritid fruit flies (direct costs to Hawaiian agriculture ~$15 million/annually, lost markets ~$300 million/annually) and the nettle moth, Darna pallivitta. I am in the process of initiating a research program in which I hope to include undergraduates with interests in chemical analysis and synthesis, and students with interests in ecology and/or organismal biology.

Research in the Teaching of Chemistry and Biology

Chemistry faculty Steve Cessna, Tara Kishbaugh, and Matt Siderhurst, along with Biology faculty Doug Graber Neufeld, Psychology faculty Jeanne Horst, and Education faculty Lori Leaman are funded by a major NSFCCLI grant to promote the enhanced learning through authentic, relevant research experiences across the biology and chemistry curriculum. Through this project, the chemistry, biology, psychology, and educations departments are involved in a unique interdisciplinary project that seeks to promote deeper, more practical learning of higher order cognitive skills (HOCs), the nature of science (NOS), and oral and written scientific communication skills. Full description of project.